Abstract
Sleep-disordered breathing (SDB) comprises different diseases characterized by abnormal respiratory patterns during sleep including obstructive sleep apnea. SDB prevalence and impact in patients with chronic respiratory infections have been only marginally studied. The purpose of this narrative review is to report the prevalence and impact of SDB in chronic respiratory infections, including cystic fibrosis (CF), bronchiectasis and mycobacterial infections, and explore the possible pathophysiological mechanisms. Common pathophysiological mechanisms, underlying SDB onset in all chronic respiratory infections, include inflammation, which plays a central role, chronic nocturnal cough and pain, excessive production of mucous plugs, presence of obstructive and/or restrictive ventilatory impairment, upper airways involvement, and comorbidities, such as alteration of nutritional status. SDB may affect about 50% of patients with bronchiectasis. The severity of the disease, e.g., patients colonized with P. aeruginosa and frequent exacerbators, as well as comorbidities, such as chronic obstructive pulmonary disease and primary ciliary dyskinesia, may impact SDB onset. SDB may also frequently complicate the clinical course of both children and adults with CF, impacting the quality of life and disease prognosis, suggesting that their routine assessment should be incorporated into the clinical evaluation of patients from the first stages of the disease regardless of suggestive symptoms, in order to avoid late diagnosis. Finally, although the prevalence of SDB in patients with mycobacterial infections is uncertain, extrapulmonary manifestations, particularly nasopharyngeal locations, and concomitant symptoms, such as body pain and depression, may act as atypical predisposing factors for their development.